body {
    width: 100%;
    min-width: 320px;
    max-width: 640px;
    margin: 0 auto;
    font-family: sans-serif;
    font-size: 14px;
    line-height: 1.5;
    color: #fff;
    /* background-color: #ccc;
    height: 2000px; */
}
div {
    
    box-sizing: border-box;
}
.clearfix:after {
    content: "";
    display: block;
    line-height: 0;
    visibility: hidden;
    height: 0;
    clear: both;
}
.app {
    height: 45px;
}
/* 设置一行的文字和图片元素 */
.app ul li {
    height: 45px;
    background-color: #333333;
    float: left;
    text-align: center !important; 
    line-height: 45px !important;
    /* vertical-align: 50% !important; */
}
a {
    color: #666;
    text-decoration: none;
}
ul {
    
    margin: 0;
    padding: 0;
    list-style: none;
}
/* 图片底部默认有空白缝隙 */
/* 出现原因：由于图片（行内块元素）要和字体的基线对齐；

解决方式：

1.通过vertical-align: top|middle|bottom;来改变对齐行内块元素的对齐方式，白色缝隙就会消失

2.将行内块元素转换成块级元素 display:block;块级元素不会和字体基线对齐。 

都添加block就很烦,所以1更好

但是全部浮动的话x也跟着浮动了所以用2 试一下*/

img {
    vertical-align: top;
}

.app ul li:nth-child(1) {
    width: 8%;
    /* position: absolute; */
    

}

.app ul li:nth-child(1) img {
    width: 10px;
    vertical-align:middle;
}

.app ul li:nth-child(2) {
    width: 10%;
}

.app ul li:nth-child(2) img {
    width: 30px;
    vertical-align: middle;
}

.app ul li:nth-child(3) {
    width: 57%;
}
.app ul li:nth-child(4) {
    width: 25%;
    background-color: #F63515;
}
/* 搜索 */
.search-wrap {
    height: 44px;
    position: fixed;
    overflow: hidden;
    width: 100%;
    min-width: 320px;
    max-width: 640px;
}

.search-btn {
    position: absolute;
    top: 0;
    left: 0;
    /* background-color: pink; */
    width: 40px;
    height: 44px;
}

.search-btn::before {
    content: "";
    display: block;
    width: 20px;
    height: 18px;
    background: url(../images/s-btn.png) no-repeat;
    background-size: 20px 18px;
    margin: 14px 0 0 15px;
}

.search-login {
    position: absolute;
    right: 0;
    top: 0;
    width: 40px;
    height: 44px;   
    /* background-color: red; */
    color: #fff;
    line-height: 44px;
}

.search {
    height: 30px;
    background-color: #fff;
    margin: 0 50px;
    /* 上下左右 */
    border-radius: 15px;
    margin-top: 7px;
    /* 会出现外边距合并,解决办法给父级添加一个overflow:hidden 
    子盒子加了margin会把父盒子带下来*/
    position: relative;
}

.jd-icon {
    width: 20px;
    height: 15px;
    position: absolute;
    top: 8px;
    left: 13px;
    background: url(../images/jd.png);
    background-size: 20px 15px;
}

.jd-icon::after {
    content: "";
    position: absolute;
    top: 0;
    right: -8px;
    display: block;
    width: 1px;
    height: 15px;
    background-color: #ccc;
}
.sou {
    width: 18px;
    height: 15px;
    position: absolute;
    top: 8px;
    left: 50px;
    background: url(../images/jd-sprites.png) no-repeat -81px 0;
    background-size: 200px;
}

.slider img {
    width: 100%;
    /* display: block; */
}
/* 品牌日 */
.brand {
    /* 盒子不用图片你也别想用 */
    overflow: hidden;
    border-radius: 10px 10px 0 0;
}
.brand div {
    width: 33.33%;
    float: left;
}

.brand div img {
    width: 100%;
}

/* nav */

nav {
    padding-top: 5px;
    display: block;
}

nav a {
    float: left;
    width: 20%;
    text-align: center;
}
nav a img {
    width: 40px;
    margin: 10px 0;
}

nav a span {
    display: block;
}

/* news */
.news {
    margin-top: 20px;
    /* display: block; */
}
.news img {
    width: 100%;
}
.news a {
    float: left;
}

.news a:nth-child(1) {
    width: 50%;
}
/* .news a:nth-child(2) {
    width: 25%;
}
.news a:nth-child(3) {
    width: 25%;
} */
.news a:nth-child(n+2) {
    width: 25%;
}
